Grinding machine



Dec. 3, 1929. DICKSQN 1,737,707

GRINDING MACHINE .Filed Aug. 3, 1925 INVENTOR BY WaV/M ATTORNEYS tion ofthe outside end surfaces Patented Dec. 3, 1929 UNITED STATES- PATENTOFFICE GEORGE DICKSON, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE BABOOCK &WILOOX COM- PANY, OF BAYONNE, NEW JERSEY, A CORPORATION OF NEW JERSEYGRINDING MACHINE Application filed August 3, 1925. Serial No. 47,706.

The invention relates to a portable device for cleaning, polishing orgrinding surfaces, such as the ends of tubes. Although the invention isespecially adapted to the preparaof tubes or the like, to adapt them tobe expanded into place, the invention is not limited to this use. It hasbeen found that where tubes are to be installed by expanding the endsthereof into boiler drums, headers, manifolds, etc., it is desirable tothoroughly clean and make smooth the exterior end surfaces of the tubesat the place and time where and when they are installed. Lathes in whichthe tubes might be prepared for installation are sometimes not availableand the tubes are sometimes of such shape or length that they could notbe placed in lathes and cleaned in that manner, thus necessitatingmanual cleaning. By the present invention, a simple portable grindingmachine is provided by which the work of cleaning the tubes forinstallation can be very rapidly and eficiently accomplished withoutrequiring a large amount of manual labor. v

In carrying out this invention, a centering shaft may be inserted intothe end of the tube that is to be round and held by means of anexpansible s eeve, or in any ot er convenient way. A frame which may berotatably mounted on the centering shaft 1s rovided preferably withresiliently held hearings for carrying the inding or polishing wheel,which may be riven by means of a flexible shaft from any convenientsource of motive ower. The tubes themselves may be clampe in vises whilethe gr nding or cleaning operation is taking place, or they may simplybe held by hand during this time. A revolving 'grindin wheel 1s slowlyrotated about the centering s aft and 1S brought 1nto grinding contactwith the outside surfaces of the tubes near the ends thereof, so as toeffect the desired cleaning of the same. In this way, tubes ofcomplicated shape, such as those having U or S bends may have theoutside ends cleaned or ground ofi to a bright metallic finish justbefore they are expanded into place where they are installed.

The invention will be understood from the description in connection withthe accompany ng drawings, in which Fig. 1 is a perspective view of thedevice; Fig. 2 is a plan v ew showing the frame; Fig. 3 is an edge viewof the same; Fig. 4 is a section therethrough and Fig. 5 shows one ofthe details.

In the drawings reference character 1 in dicates a rectangular framethrough the respective ends of which threaded holes 2 pass. Threadedadjusting screws 3 with lmurled handles 4 extend through the holes 2 andare provided with collars 5, against which compression springs press.The rectangular frame 1 is provided with a transverse shaft or axis 6,and a bearing 7 having a hole 8 therethrough is pivoted on the shaft 6.The side of the bearing 7 opposite the axis 6 is V-shaped (Fig. 4) asshown at 9. A slidable bearing 10 aving an opening 11 therethrough ismounted in the frame 1 and is provided with a socket for the threadedpin 12, which carries an adjustable washer 13. The bearing 10 isprovided on one side thereof with flanges 14 which bear against thesmooth surface 15 along one side of the frame 1. A removable plate 16 isattached to the bearing 10 on the side opposite the flanges 14 and is ofsufiicient width to provide, in effect, flanges for the bearing 10correspondin to the flanges 14, but on the opposite side 0 the bearin10, and slidable along the smooth surface 1 of the frame 1. A slideblock or groove block 18 is also mounted in the frame 1 and is providedwith a V-shaped groove 19 in which the V- shaped end 9 of the bearing 7seats. The block 18 is provided with flanges 20 on one sidecorresponding to the flanges 14 of the bearing 10, and-'t is provided onthe other side with a detachable plate 21 corresponding to thedetachable plate 16. These plates 16 and 21 can be detached so as topermit ready removal of the block 18 and bearing 10 from the frame 1.

A compression spring 22 is interposed between the collar 5 and the block18, one end of said spring being seated in the socket 23 in the block18, said spring surrounding the screw 3 for a short distance. A spring24: is interposed between the collar 13 and the hearing 7, one end ofthe spring being seated in the socket in said bearing and said springsurrounding the pin 12 for a short distance. A spring 26 is interposedbetween the hearing 10 and the collar 5, said spring surrounding thescrew 3 for a short distance. Bushings 27 of various lengths (two ofwhich are shown in Fig. 5) may be placed on the screws 3 to limit theinward adjustment of these screws as the handle portions 4 contacttherewith. A centering shaft 28 (Fig. 1) passes through the opening 11in bearing 10 and is inserted in the end of the tube 29 and may besecured therein, for example, by means of the expanding sleeve 30.The'shaft 28 may be provided with a transverse hole 31 near the endthereof, so that a suitable pin can be inserted in this hole to tightenthe shaft to the tube 29 by turning same into the expanding plug and toprevent the frame carrying the bearing 10 from becoming displaced. Ashaft 32 carrying the grinding wheel 33 passes through the bearing 7 andis connected to a flexible shaft 35, which may be driven by means of themotor 34.

in the tube to be ground, the

The operation is as follows: The end of the centering shaft 28 isinserted in the tube 29 and is secured therein by means of theexpansible sleeve or bushing 30, so that the shaft 28 is alined with theend of the tube 29. The frame 1 is rotatably mounted on the shaft 28 andcarries through the bearing 7 the grinding or cleaning or polishingelement 33, which may be rapidly rotated by means of the motor 34. Thescrews 4 and collar 13 are adjusted to place the proper tension upon thesprings and cause the bearings 7 and 10 to be adjusted to the properdistance apart, so that the shafts 28 and 32 will be in substantialparallelism, the size of the grinding wheel 33 being such that thisresult can be obtained.

The wheel 33 is set in motion and the frame 1 is gradually turnedmanually around the shaft 28, thus bringing the grinding wheel 33 intospring pressed or resilient contact with all portions of the outersurface of the end of the tube that are to be polished or cleaned.

The desired pressure of the grinding wheel against the outside surfaceof the tube may be maintained by, adjustment of the springs, and thepivotal mounting of the bearing 7 on the axis 6 permits relativemovement of the shaft 32 with respect to the shaft 28 to compensate forany irregularities that may be present V-shaped end 9 of the hearingriding along the sides of the V-shaped groove 19 of the slide block 18during temporary displacement of the shaft 32. By utilizing thecompression springs for producing the desired pressure of the grindingwheel against the surface to be ground,

the grinding operation can be satisfactorily performed even in caseswhere the centering shaft 28 is not mounted in perfect alinement withthe end or exterior surface of the tube. The grinding wheels may even bemade of hollow metal and may be provided with air cushion rims so as toenhance the yielding action of the grinding surfaces.

In using this device, one adjustment is all that is necessary for a setof tubes of the same size, as the device can be applied to the ends ofthe respective tubes simply by inserting and securing the shaft 28, theshafts 28 and 32 being slightly spread. apart during the time thegrinder is being placed in proper grinding position.

I claim: 7

1. In a grinding machine, a frame having parallel side pieces carryingtwo bearings between said side pieces, means to support said framerotatably in relation to the object to be ground, said frame carrying agrinder supported in one of said bearings.

2In a grinding machine, a frame having parallel side pieces carrying twobearings, one of which is pivoted to said frame and the other isslidable thereon, means to support said frame rotatably by means of saidslidable bearing in relation to the object to be ground, said framecarrying a grinder in said pivoted bearing. 2

3. In a grinding machine, a frame having parallel side pieces carryingtwo bearings, one of which is pivoted to said frame and the other isslidable thereon, said slidable bearing being resiliently held in place,means to support said frame rotatably by means of said slidable bearingin relation to the object to be ground, said frame carrying a grinder insaid pivoted bearing.

4. In a grinding machine, a frame having parallelside pieces carryingtwo bearings, one of which is pivoted to said frame and the other isslidable thereon, said pivoted bearing being spring retained in normalposition, means to support said frame rotatably by means of saidslidable bearin in relation to the object to be ground, said ramecarrying a grinder in said pivoted bearing.

5. In a grinding machine, a frame having parallel side pieces carryingtwo bearings, a spring tending to maintain one of said bearings parallelto the other, means to support said frame rotatably in relation to the Iobject to be ground, said frame carrying a grinder in one of said bearins.

6. In a grinding machine, a rame carrying two bearings, one of which ispivoted to said frame, and the other is slidable thereon, said bearingsbeing held resiliently in place, means to adjust distances between saidbearings, and means to support said frame rotatably in relation to anobject to be ground, said frame carrying a grinder in said pivotedbearing.

7 In a grinding machine, a frame oar ing bearings one of which isslidable in said frame and is resiliently held in place in said frameand the other one of which is pivoted in said frame, said bearingsbeingsadapted to Carry substantially parallel sha 8. In a grindingmachine, a frame carr ing bearings one of which is slidable in sa1dframe and is resiliently held in place in said frame and the other oneof which is pivoted in said frame, said bearings being adapted to carrysubstantially parallel shafts, and a grinding wheel carried by one ofsaid shafts.

9. In a grinding machine, a frame carrying bearings one of which isslidable in said frame and spring pressed on opposite sides and theother one of which is pivoted in said frame, and substantially parallelshafts carried in said bearings.

10. In a grinding machine, a frame carrying bearings one of which isslidable in said frame and is resiliently held in place in'said frameand the other one of which is pivoted in said frame, said bearings beingadapted to carry substantially parallel shafts and being adjustable todifferent distances apart in said frame.

11. In a grinding machine, a frame carrying bearings one of which isslidable in said frame and is resiliently held in place in said frameand the other one of which is pivoted in said frame, said bearings beingadapted to carry substantially parallel shafts, a grinding wheelcarriedby one of said shafts. and the other shaft holding its bearing inalignment with the center line of the object to be ground.

12. In a grlnding machine, an elongated frame carrying a bearing aroundwhich said frame may be revolved, said bearing being adjustablelongitudinally of said frame and resiliently held in place, a secondbearing pivoted in said frame and a grindingelement having a shaftextending through said second bearing.

13. In a grinding machine, an elongated frame carrying a bearing aroundwhich said frame may be revolved, said bearing being adjustablelongitudinally of said frame and resiliently held in place, a secondbearing piv oted in said frame and adapted to carry the shaft of agrinding element, one of said bearings being on one side of the middlepoint of said frame and the other one on the other side of said middleint.

EORGE DICKSON.

